Exploring two methods of usability testing: concurrent versus retrospective think-aloud protocols

Think-aloud protocols are commonly used for the usability testing of instructional documents, Web sites and interfaces. This paper addresses the benefits and drawbacks of two think-aloud variations: the traditional concurrent think-aloud method and the less familiar retrospective think-aloud protocols. It also offers an outline of a long-term research project designed to empirically investigate the value of both variants. The results of a first comparative study indicate that, although the two methods have distinct differences, they do seem to produce a similar outcome. A more detailed description of the results will be offered during the presentation

Analyzing the interaction between facilitator and participants in two variants of the think-aloud method.

This paper focuses on the interaction between test participants and test facilitator in two variants of the think-aloud method. In a first, explorative study, we analyzed think-aloud transcripts from two usability tests: a concurrent think-aloud test and a constructive interaction test. The results of our analysis show that while the participants in both studies never explicitly addressed the facilitator, the think-aloud participants showed more signs of awareness of the facilitator than the participants in the constructive interaction test. This finding may have practical implications for the validity of the two methods

Why should i comply? Sellers' accounts for (non-)compliance with legal age limits for alcohol sales

Background\ud Availability is an important predictor of early and excessive alcohol consumption by adolescents. Many countries have implemented age limits to prevent underage purchases of alcohol. However, shop-floor compliance with these age limits appears to be problematic. This study addresses the issue of non-compliance with age limits. Which measures do vendors take to avoid underage alcohol sales, and what do they report as important reasons to comply or not with age limits for alcohol sales? \ud \ud Methods\ud Open-ended telephone interviews were conducted with store managers selling alcohol (N = 106). Prior to the interviews, all outlets were visited by an underage mystery shopper in order to measure compliance with the legal age limits on alcohol sales. The interview results are compared against actual compliance rates. \ud \ud Results\ud Several measures have been taken to prevent underage sales, but the compliance level is low. Furthermore, open coding resulted in 19 themes, representing both valid and invalid arguments, that vendors mentioned as relevant to their decisions of whether to comply with the law. Compliance with age limits is dependent on the knowledge of the rules and the ability and motivation to follow the rules. The ability aspect in particular seems to be problematic, but in many cases, the motivation to actively comply with the age limits is lacking. \ud \ud Conclusions\ud To enhance compliance, it is important to raise the awareness of the importance of age limits and to connect possible violations of the regulations to negative consequences\u

Moderating the neutralist–selectionist debate: exactly which propositions are we debating, and which arguments are valid?

Half a century after its foundation, the neutral theory of molecular evolution continues to attract controversy. The debate has been hampered by the coexistence of different interpretations of the core proposition of the neutral theory, the ‘neutral mutation–random drift’ hypothesis. In this review, we trace the origins of these ambiguities and suggest potential solutions. We highlight the difference between the original, the revised and the nearly neutral hypothesis, and re-emphasise that none of them equates to the null hypothesis of strict neutrality. We distinguish the neutral hypothesis of protein evolution, the main focus of the ongoing debate, from the neutral hypotheses of genomic and functional DNA evolution, which for many species are generally accepted. We advocate a further distinction between a narrow and an extended neutral hypothesis (of which the latter posits that random non-conservative amino acid substitutions can cause non-ecological phenotypic divergence), and we discuss the implications for evolutionary biology beyond the domain of molecular evolution. We furthermore point out that the debate has widened from its initial focus on point mutations, and also concerns the fitness effects of large-scale mutations, which can alter the dosage of genes and regulatory sequences. We evaluate the validity of neutralist and selectionist arguments and find that the tested predictions, apart from being sensitive to violation of underlying assumptions, are often derived from the null hypothesis of strict neutrality, or equally consistent with the opposing selectionist hypothesis, except when assuming molecular panselectionism. Our review aims to facilitate a constructive neutralist–selectionist debate, and thereby to contribute to answering a key question of evolutionary biology: what proportions of amino acid and nucleotide substitutions and polymorphisms are adaptive?

Effects of Media Ratings on Children and Adolescents: A Litmus Test of the Forbidden Fruit Effect

Media ratings serve to inform parents about and protect minors from violent or otherwise harmful media content. Most of these systems use age pictograms and content warning pictograms for entertainment products. An experiment was conducted to investigate whether these pictograms, contrary to their purpose, have an appealing effect on children and adolescents. Compared to prior studies into this ‘‘forbidden fruit effect’’ concerning DVDs and games, more realistic materials were used. In the experiment, 322 elementary school students (9–11 years) and 335 high school students (13–15 years) were exposed to 10 DVD or game covers and asked to judge the products’ attractiveness. The results show that the pictograms did not increase the attractiveness of games and DVDs for children and adolescents

Widespread transfer of resistance genes between bacterial species in an intensive care unit: implications for hospital epidemiology

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Correction:Cost-effectiveness of apixaban compared to other anticoagulants in patients with atrial fibrillation in the real-world and trial settings

[This corrects the article DOI: 10.1371/journal.pone.0222658.]

Companion Animals as a Source of Viruses for Human Beings and Food Production Animals

Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective basis for more in-depth analysis of the risk of companion animals as sources of viruses for human and food production animal health